The present invention relates generally to railroad right of way maintenance equipment, and specifically to machinery for forming and/or shaping rail track ballast in conjunction with railroad track repair, replacement or reconditioning.
Crushed rock rail ballast forms the support bed into which rail ties are inserted for receiving tie plates, spikes or other fasteners, and ultimately the rails. Ballast supports the weight of loaded trains, and also is sufficiently porous to allow the drainage of standing water from the typically wooden ties. Also, the ballast provides the ability to maintain a constant rail/ground displacement or grading over varying terrain and soil conditions.
During railway maintenance operations, including but not limited to tamping, tie replacement, rail replacement or the like, the ballast becomes disrupted and must be reshaped. The optimal shape of rail ballast is a generally level upper surface in which the ties are embedded, and a pair of gradually sloping sides which flare out from ends of the rail ties at a specified angle or angular range which is generally constant across the railroad industry. However, depending on the application and available space, the angle of the ballast may vary.
To achieve the desired angular slope, ballast regulators are employed, which are either self-propelled or towed, and feature at least one articulated, fluid-powered wing arm having at least one blade attached. Similar in function to a highway snowplow, the blade is oriented at a desired angle and is pushed by the ballast regulator through the ballast as the regulator moves along the track. To facilitate the reuse of ballast stones dislodged during the regulation of the ballast, it is typical for a wing to include a main outer door and laterally oriented template doors. The template doors are pivotally connected to side edges of the outer door, and through the use of fluid-powered cylinders, the position of the template doors relative to the outer door can be adjusted to form “C-”, “U-” or similarly shaped configurations to retain a supply of disrupted ballast as the regulator moves along the track. In this way, there is sufficient ballast to fill in any depressions encountered to maintain a uniform slope. An exemplary rail ballast regulator is disclosed in U.S. Pat. No. 6,883,436, which is incorporated by reference.
One drawback of conventional ballast regulators is that when they are transported from one maintenance location to another, they must be towed on a trailer by a semi-tractor. Due to the size and/or weight of the regulator, special oversize use permits are often required for on-road transport by the U.S. Department of Transportation for carrying the machine on a highway. Moreover, once the machine reaches its destination, a heavy-duty lifting machine such as a crane, is needed to move the regulator onto the railway track for operation. Accordingly, the transportation of conventional rail ballast regulators is inconvenient and cumbersome, and incurs high shipping costs due to the above-described difficulties. Also, in some cases, these transportation difficulties make it less convenient for locating regulators sufficiently close to the desired worksite.
Another drawback of conventional ballast regulators is that the wing or plow blades are subject to extreme abrasion as they work through the ballast. Sacrificial wear plates are commonly fastened to the main blades for exposure to the ballast while protecting the blades. These plates are fastened to the blade sandwich style using threaded bolts and nuts. However, through extended exposure to rail ballast, the nuts and/or bolt heads often become worn down so that the facets are obliterated, or in any event are unsuitable for removal using conventional tools. Thus conventional maintenance of regulators includes using torches or other heavy equipment for removing the blade wear plates. Another disadvantage of conventional wing wear plates is that more than one operator is required for placing them on the wing blade. The plates often weigh as much as 50 pounds, and must be held in place by one operator so that the fasteners can be inserted through corresponding holes in the plate and blade by the other operator.
Thus, there is a need for an improved rail regulator that is roadworthy without requiring special use permits. There is also a need for an improved regulator blade where the wear plates are resistant to ballast abrasion so that replacement is facilitated.